When Giulia says "La neve è bianca" and John says "The snow is white", they both mean the same thing despite of speaking different languages. That is because they both express the proposition <snow is white>. Their utterances express their beliefs in the same proposition. And that proposition is true because snow is actually white.

Propositions are abstract objects that are traditionally considered to play the three roles just mentioned: they are the bearers of truth-values, contents of mental states, and contents of utterances. Since the early 20th Century propositions were taken to have their truth-values absolutely. However, the development of possible world semantics showed that propositions should be understood as true or false relative to a possible world. Consequent developments in modal logics suggested that we may further relativise propositions to e.g. times or moral standards. The idea is that e.g. "Torture is wrong" does not express a proposition that is true or false absolutely, but only relative to certain moral standards. Thus, John might say "Torture is wrong", Jill say "Torture is not wrong", and both speak the truth since the propositions they express are evaluated for truth relative to different moral standards.

The question is, do these modifications in the notion of propositions as truth-bearers mean the contents of thoughts and utterances are equally relative? Or, should we distinguish two different kinds of propositions, the absolute and the relative ones which play different roles? The former view has gained popularity recently, with many philosophers arguing that thought and utterance contents are best understood as relative propositions as well. Many claim that it helps make sense of traditional relativism, i.e. the view that some claims are "true for me, false for you". These philosophers have argued that propositions should be relativised to e.g. standards of taste or knowledge or moral standards, and that the resulting forms of relativism help us understand how these features are "subjective".

This course delves into the topic of relative propositions: the motivations behind introducing them, the arguments for relativising propositions to further features, and the consequences of taking relative propositions as the contents of thought and communication.